Wafer epitaxial film thickness measuring equipment

Abstract

The invention provides wafer epitaxial film thickness measuring equipment, which comprises a rack, and a turnover mechanism, a correction mechanism and a measuring mechanism which are arranged in a measuring chamber in the rack, a feeding table and a discharging table are arranged on the outer side of the rack, and the turnover mechanism is turned over among the correction mechanism, the measuring mechanism, a material taking port of the feeding table and a material taking port of the discharging table and is used for conveying materials; the correcting mechanism and the measuring mechanism are arranged around the outer side of the turnover mechanism; the correction mechanism comprises a correction table and a sensor group, the correction table is provided with a positioning assembly I for positioning the position of the wafer, the sensor group is used for detecting the reference position of the wafer, and the correction table can correct the position of the wafer according to the detected reference position; the measuring mechanism comprises a measuring table and a spectrum measuring instrument, the spectrum measuring instrument is used for measuring the thickness of the epitaxial film of the wafer, and the measuring table is used for driving the wafer to translate and rotate. According to the invention, the position of the wafer is corrected through the correction mechanism before measurement, so that the accuracy and stability of measurement are ensured, the measurement steps are simplified, and the production efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to a wafer epitaxial film thickness measuring device. Background Art

[0002] During the manufacturing process of semiconductor wafers, different epitaxial film layers need to be formed, and the thickness of each epitaxial film layer is also different. The epitaxial film thickness is one of the important parameters that affect the physical properties of the wafer. In order to accurately realize the circuit function, it is necessary to accurately control the thickness of each epitaxial film formed on the surface of the semiconductor wafer to prevent the thickness of the formed epitaxial film from being too thick or too thin, causing the semiconductor wafer to not meet the requirements and affecting the yield of the semiconductor wafer. Therefore, in order to monitor the thickness of the epitaxial film, the thickness of the epitaxial film is usually measured after it is formed. If the thickness is abnormal, corresponding improvement measures should be taken immediately.

[0003] Existing measuring equipment lacks a correction mechanism, which causes a certain position deviation of the wafer in the subsequent measurement position, which in turn has a certain impact on the measurement results of the epitaxial film thickness of the wafer and subsequent processing; or the measuring equipment corrects the position by moving the measuring instrument. Although this method corrects the position, it makes the measurement process complicated and cumbersome, affecting the stability of the measurement results.

[0004] In addition, in order to measure the overall epitaxial film thickness distribution trend on the semiconductor wafer surface, multiple measurement points need to be set on the semiconductor wafer according to different process requirements. The measurement table of existing measurement equipment realizes the position change of the wafer measurement point on the measurement table by setting an XY moving module, but this method requires multiple displacements, which is cumbersome, time-consuming, and inefficient, thus affecting the overall production efficiency. Summary of the invention

[0005] The present invention aims to provide a wafer epitaxial film thickness measurement device to overcome the deficiencies in the prior art.

[0006] In order to solve the above technical problems, the technical solution of the present invention is: a wafer epitaxial film thickness measurement device, including a frame, a turnover mechanism, a correction mechanism, and a measuring mechanism, wherein a closed measuring chamber is arranged in the frame, and a loading platform and a unloading platform are arranged in parallel on the outside of the frame, and the loading platform and the unloading platform are both provided with a material taking port connected to the measuring chamber, and the turnover mechanism is arranged in the measuring chamber, and circulates between the correction mechanism, the measuring mechanism and the loading platform and the unloading platform to transport materials; the correction mechanism and the measuring mechanism are also arranged in the measuring chamber, and are arranged around the measuring chamber. The correction mechanism is arranged outside the rotating mechanism; the correction mechanism includes a correction platform and a sensor group, the correction platform is used to place the wafer, and a positioning component for positioning the wafer on the correction platform is provided on the correction platform, the sensor group is arranged on the correction platform, and is used to detect the reference position of the wafer, and the correction platform can drive the wafer to rotate according to the detected reference position to correct the position of the wafer; the measuring mechanism includes a measuring platform and a spectrometer, the spectrometer is arranged above the measuring platform, and is used to measure the thickness of the epitaxial film of the wafer, the measuring platform is used to place the wafer, and can drive the wafer to translate and rotate.

[0007] Furthermore, in the above-mentioned wafer epitaxial film thickness measuring equipment, the measuring chamber is divided into measuring chamber one and measuring chamber two by a partition, the turnover mechanism and the correction mechanism are arranged in the measuring chamber one, the measuring mechanism is arranged in the measuring chamber two, and the partition is provided with a working groove for the mechanical arm of the turnover mechanism to pass through; the tops of the measuring chambers one and two are both provided with fans for clean measuring rooms.

[0008] Furthermore, in the above-mentioned wafer epitaxial film thickness measuring equipment, the loading table and the unloading table have the same structure, including a movable table and a material box arranged on the movable table, the movable table is attached to the outside of the frame, the material box is divided into multiple wafer placement areas, the material box covers the outside of the material port, and the material box opening is connected to the material port.

[0009] Furthermore, in the above-mentioned wafer epitaxial film thickness measuring equipment, the turnover mechanism includes a moving module 1 and a robotic arm base. The moving module 1 is fixed at the bottom of the frame, and a robotic arm base is provided at its output end. A lifting assembly is provided in the robotic arm base, and two robotic arms are provided at the output end of the lifting assembly. The two robotic arms take and put materials alternately.

[0010] Furthermore, in the above-mentioned wafer epitaxial film thickness measuring equipment, the turnover mechanism also includes a clamping assembly arranged on the mechanical arm, the clamping assembly includes a connecting arm, a telescopic rod, a push plate, and a support plate, the connecting arm is connected to the output end of the mechanical arm, the support plate is a Y-shaped fork plate, whose main body end is connected to the connecting arm, and the top surfaces of the two fork-shaped plates at its forked end are provided with a support block 1, the push plate is arranged on the main body end of the support plate, and is slidably connected to the support plate through the telescopic rod inserted on the connecting arm, the support plate is also provided with a slide groove for guiding the sliding of the push plate, and the main body end of the support plate is also provided with a support block 2 located on both sides of the push plate, the top surfaces of the support blocks 1 and 2 are both provided with an arc-shaped support surface, the support surface is used to support the wafer, and the middle part of the support surface of the support block 1 is also provided with a stop block protruding from the support surface, the push plate and the stop block cooperate to position the wafer placed on the support surface.

[0011] Furthermore, in the above-mentioned wafer epitaxial film thickness measuring equipment, the correction mechanism also includes an identification component arranged on one side of the correction table, the identification component is used to identify the wafer mark, including an identifier, a mounting seat, an adjustment seat, and a vertical pole, the vertical pole is fixed to the bottom of the frame, the identifier is fixed on the mounting seat, the mounting seat is connected to the adjustment seat through a connecting rod, the adjustment seat is clamped on the vertical pole, and the identifier can adjust the position of the identifier relative to the correction table through the adjusting seat and the connecting rod, including height, distance, and angle adjustment.

[0012] Furthermore, in the above-mentioned wafer epitaxial film thickness measuring equipment, the positioning component one includes a support block three and a telescopic clamp block. A plurality of support blocks three are arranged along the circumferential direction on the top of the correction table, and a plurality of telescopic clamp blocks are arranged along the circumferential direction on the outer side of the correction table. Each support block three is arranged one-to-one with each telescopic clamp block, and a supporting inclined surface is provided on the top of the support block three, and an arc-shaped clamping groove is provided on the clamping end of the telescopic clamp block.

[0013] Furthermore, in the above-mentioned wafer epitaxial film thickness measuring equipment, a correction base is provided below the correction table, and a telescopic module for driving a plurality of telescopic clamps to move radially along the correction table and a rotating component for driving the correction table to rotate along the Z direction are provided in the correction base.

[0014] Material toggling mechanism, its both sides respectively have a cylinder pressure, and the cylinder pressure bar connects swing arm, and the swing arm end face has hook portion, and a bar passes position between the end of two swing arms and the hook portion.

[0015] Furthermore, in the above-mentioned wafer epitaxial film thickness measuring equipment, the measuring mechanism also includes a base, a mobile module 2, and a rotary motor located below the measuring platform. The mobile module 2 is provided above one side of the base, and a platform for installing a spectrometer is provided on the other side. The rotary motor is fixed to the mobile end of the mobile module 2 through a motor mounting seat, and the measuring platform is connected to the output end of the rotary motor; a protective cover covering the rotary motor is also provided between the mobile module 2 and the measuring platform; and a gold mirror assembly for calibrating the optical path of the spectrometer is also provided on one side of the motor mounting seat. Preferably, the gold mirror assembly includes a lifting cylinder and a gold mirror, the lifting cylinder is fixed to the motor mounting seat through a cylinder mounting seat, the gold mirror is connected to the output end of the lifting cylinder through a gold mirror mounting seat, and the gold mirror can be moved up and down by the lifting cylinder, thereby adjusting the position of the gold mirror.

[0016] Furthermore, in the above-mentioned wafer epitaxial film thickness measurement equipment, the base is an air-floating platform, and the four corners of the bottom are provided with air-floating shock absorbers fixed on the frame, and the air-floating shock absorbers are connected to an external air source.

[0017] The present invention also provides a working method of a wafer epitaxial film thickness measuring device, comprising the following steps:

[0018] S1, loading, the robot arm takes a wafer from the loading box on the loading table and places it on the calibration table, and then the positioning component is started to position and fix the wafer on the calibration table;

[0019] S2, calibration, the calibration mechanism calibrates the position of the wafer according to the detected reference position, and the recognition component recognizes and records the wafer mark;

[0020] S3, material picking, the robot arm goes to the calibration table to pick up the material, the clamping assembly on the robot arm goes to the calibration table to clamp the wafer, and then the positioning assembly 1 releases the positioning of the wafer to ensure that the wafer does not shift during the material picking process, and then the robot arm places it on the measuring table, and the positioning assembly 2 positions and fixes the wafer on the measuring table;

[0021] S4, measurement, the spectrometer measures the epitaxial film thickness of the wafer according to the set measurement points, and binds the measurement results to the corresponding wafer marks; while measuring, the calibration mechanism can calibrate again;

[0022] S5, unloading. After the measurement is completed, the robot arm places the measured wafer on the unloading table.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention corrects the measured position by a correction mechanism before measurement, and does not need to correct the position by moving the measuring instrument, thereby ensuring the accuracy and stability of the measurement; the correction mechanism is separately arranged from the measuring mechanism, and the correction and measurement can be carried out simultaneously, thereby ensuring production efficiency; and the measuring mechanism can simplify the measurement operation steps, reduce the measurement time, and improve the production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 It is a schematic diagram of the external structure of the wafer epitaxial film thickness measuring device of the present invention;

[0026] Figure 2 It is a schematic diagram of the internal structure of the wafer epitaxial film thickness measurement device of the present invention;

[0027] Figure 3 for Figure 2 A top view of

[0028] Figure 4 It is a schematic diagram of the structure of the turnover mechanism of the wafer epitaxial film thickness measuring device of the present invention;

[0029] Figure 5 It is a schematic structural diagram of a clamping assembly of a wafer epitaxial film thickness measuring device of the present invention;

[0030] Figure 6 It is a schematic structural diagram of a correction mechanism of a wafer epitaxial film thickness measuring device according to the present invention;

[0031] Figure 7It is a schematic diagram of the structure of the measuring mechanism of the wafer epitaxial film thickness measuring device of the present invention;

[0032] Figure 8 It is a schematic diagram of the partial structure of the measuring mechanism of the wafer epitaxial film thickness measuring device of the present invention;

[0033] Fig. 9 The structure of the push assembly of the wafer epitaxial film thickness measurement device of the present invention is shown in FIG. Figure 1 ;

[0034] Fig.10 The structure of the push assembly of the wafer epitaxial film thickness measurement device of the present invention is shown in FIG. Figure 2 ;

[0035] In the figure: 1, frame; 11, partition; 12, measuring room 1; 13, measuring room 2;

[0036] 2. Turnover mechanism; 21. Mobile module 1; 22. Robot arm base; 23. Lifting assembly; 24. Robot arm; 25. Clamping assembly; 251. Connecting arm; 252. Telescopic rod; 253. Push plate; 254. Support plate; 2541. Slide; 255. Support block 1; 2551. Stop block; 256. Support block 2;

[0037] 3. Correction mechanism; 31. Correction platform; 32. Sensor group; 33. Positioning component one; 331. Support block three; 332. Telescopic clamping block; 34. Correction base; 35. Identification component; 351. Identifier; 352. Mounting seat; 353. Adjustment seat; 354. Vertical pole; 355. Connecting rod;

[0038] 4. Measuring mechanism; 41. Measuring table; 42. Spectrometer; 43. Positioning assembly II; 431. Fixed chuck; 4311. Stop table; 432. Movable chuck; 44. Push assembly; 441. Push cylinder; 442. Wheel seat; 443. Push wheel; 444. Push rod; 445. Slide seat; 446. Slide rail; 447. Push rod; 45. Base; 46. Mobile module II; 47. Rotating motor; 471. Motor mounting seat; 472. Protective cover; 48. Gold mirror assembly; 481. Lifting cylinder; 482. Gold mirror; 49. Air-floating shock absorber;

[0039] 5. Loading table; 51. Moving table frame; 52. Material box; 6. Unloading table;

[0040] 7. Fan. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Example 1

[0043] like Figure 1-10As shown, a wafer epitaxial film thickness measuring device includes a frame 1, a turnover mechanism 2, a correction mechanism 3, and a measuring mechanism 4. The frame 1 is provided with a sealing plate and a switchable door on the outside, and the inner cavity of the frame 1 is set as a closed measuring room. The outside of the frame 1 is provided with a loading table 5, an unloading table 6 and a display screen arranged in parallel. The loading table 5 and the unloading table 6 are both provided with a material taking port connected to the measuring room. The turnover mechanism 2 is arranged in the measuring room, and circulates between the correction mechanism 3, the measuring mechanism 4 and the material taking ports of the loading table 5 and the unloading table 6 for conveying materials; the correction mechanism 3 and the measuring mechanism 4 are also arranged in the measuring room and are arranged around the outside of the turnover mechanism 2; the correction mechanism 3 includes a correction table 31 and a sensor group 32. The correction table 31 is used to place wafers, and is provided with a positioning component 33 for positioning the wafer on the correction table 31. The sensor group 32 is arranged on the correction table 31. , used to detect the reference position of the wafer. The sensor group in this embodiment can not only detect the reference position of the wafer, but also detect whether there is a wafer on the correction table. The reference position can be a notch, missing edge and other features on the wafer. In this embodiment, the notch of the wafer is used as the detection reference position, but it is not limited to this. The correction table 31 can drive the wafer to rotate according to the detected reference position to correct the position of the wafer, including correcting the center of the wafer and the position of the reference position relative to the center of the wafer. The center of the wafer is corrected by positioning component 1, and the position of the reference position relative to the center of the wafer can be corrected by rotating the correction table to ensure the accuracy of the initial measurement point position and facilitate subsequent measurements; the measuring mechanism 4 includes a measuring table 41 and a spectrometer 42. The spectrometer 42 is arranged above the measuring table 41 and is used to measure the thickness of the epitaxial film of the wafer. The measuring table 41 is used to place the wafer and can drive the wafer to translate and rotate. In this embodiment, the measuring method of the measuring mechanism 4 is as follows: a plurality of measuring points are set on the wafer, and the plurality of measuring points are distributed along the circumference of a plurality of concentric circles, the concentric circles are concentric with the wafer, and the initial measuring point position is set on the innermost or outermost concentric circle, and the relative position of the initial measuring point relative to the center of the wafer and the reference position has been calibrated by the calibration mechanism 3 before the measurement; during the measurement, the spectrometer 42 is located directly above the initial measuring point, and the measurement is started from the initial measuring point first, and after the measurement, the measuring platform 41 is rotated by an angle, and other measuring points on the circumference where the initial measuring point is located are measured in sequence; after measuring the measuring points on the circumference of one concentric circle, the measuring platform 41 is translated so that the second concentric circle is located within the range of the spectrometer 42, and then the measurement of the measuring points on the second concentric circle is completed in sequence until all the measuring points are measured. In summary, the present invention corrects the measured position by the correction mechanism 3 before measurement, and does not need to correct the position by moving the measuring instrument, thereby ensuring the accuracy and stability of the measurement. The correction mechanism 3 and the measuring mechanism 4 are separately arranged, and the correction and measurement can be carried out simultaneously, thereby ensuring the production efficiency. The measuring mechanism can simplify the measurement operation steps, reduce the measurement time, and improve the production efficiency.

[0044] In the above structure, if Figure 1-3 As shown, the measuring chamber is divided into a measuring chamber 1 12 and a measuring chamber 2 13 by a partition 11, and the partition 11 is installed on the frame in the middle of the frame 1, the turnover mechanism 2 and the correction mechanism 3 are arranged in the measuring chamber 1 12, and the measuring mechanism 4 is arranged in the measuring chamber 2 13, and the partition 12 is provided with a working slot for the mechanical arm 23 of the turnover mechanism 2 to pass through; the setting of the measuring chamber 1 12 and the measuring chamber 2 13 can avoid mutual influence, and the measuring mechanism 4 adopts a spectrometer, and its measurement principle is through reflected light detection. The measurement chamber is separated to make the measurement more stable and accurate; the tops of the measuring chambers 1 12 and 13 are both provided with fans 7 for clean measuring chambers. The setting of the fans 7 ensures that the measuring chambers are clean, ensures that the wafers are measured in a clean environment, avoids contamination of the wafers during the measurement process, and ensures the accuracy of the measurement.

[0045] Among them, Figure 1 , 3 As shown, the loading platform 5 and the unloading platform 6 have the same structure, including a mobile platform 51 and a material box 52 arranged on the mobile platform 51. The mobile platform 51 is attached to the outside of the frame 1. The material box 52 is divided into multiple wafer placement areas. The material box 52 covers the outside of the material extraction port, and the opening of the material box 52 is connected to the material extraction port. The mobile platform 51 can facilitate the movement of the loading platform and the unloading platform, has good flexibility, and the material extraction port is closed by the material box 52 to ensure the closure of the measurement chamber.

[0046] like Figure 3 , 4 As shown, the turnover mechanism 2 includes a mobile module 21 and a mechanical arm base 22. The mobile module 21 is fixed at the bottom of the frame 1, and the output end thereof is provided with a mechanical arm base 22. The mechanical arm base 22 is provided with a lifting assembly 23. The output end of the lifting assembly 23 is provided with two mechanical arms 24. The two mechanical arms 24 take and discharge materials alternately. The action of each mechanical arm 24 can be set according to actual conditions, which can reduce the loading and unloading time and improve production efficiency. The X and Z direction translation of the turnover mechanism 2 can be realized by setting the lifting assembly 23 and the mobile module 21. The mechanical arm 24 is a multi-axis mechanical arm, which has multiple degrees of freedom. It can flexibly change the alternating position between the material taking ports of the correction mechanism 3, the measuring mechanism 4, and the loading platform 5 and the unloading platform 6, which is convenient for taking and discharging materials.

[0047] Example 2

[0048] Based on the structure of Example 1, Figure 4 , 5As shown, the turnover mechanism 2 also includes a clamping assembly 25 arranged on the mechanical arm 24, and the clamping assembly 25 includes a connecting arm 251, a telescopic rod 252, a push plate 253, and a support plate 254. The connecting arm 251 is connected to the output end of the mechanical arm 24, and the support plate 254 is a Y-shaped fork plate, whose main end is connected to the connecting arm 251, and the top surfaces of the two fork-shaped plates at the forked end are provided with a support block 255. The push plate 253 is arranged at the main end of the support plate 254, and is connected to the support plate 254 through the telescopic rod 252 inserted on the connecting arm 251. The support plate 254 is slidably connected, and the support plate 254 is also provided with a slide groove 2541 for guiding the push plate 253 to slide. The main end of the support plate 254 is also provided with a support block 256 located on both sides of the push plate 253. The top surfaces of the support blocks 1 255 and 256 are both provided with arc-shaped support surfaces, which play a supporting and guiding role. The support surface is used to support the wafer, and the middle part of the support surface of the support block 1 255 is also provided with a stop block 2551 protruding from the support surface. The push plate 253 cooperates with the stop block 2551 to position the wafer placed on the support surface. When the mechanical arm 24 clamps the wafer, the bifurcated end of the support plate 254 extends into the bottom of the wafer, so that the wafer is located on the four support surfaces of the support blocks 1 255 and 256, and then the telescopic rod 252 is started to push the push plate 253 to move toward the stop block 2551, and the wafer is pressed tightly between the outer side of the stop block 2551 and the push plate 253.

[0049] like Figure 6 As shown, the correction mechanism 3 also includes an identification component 35 disposed on one side of the correction platform 31, and the identification component 35 is used to identify the wafer mark, including an identifier 351, a mounting seat 352, an adjustment seat 353, and a vertical rod 354. The vertical rod 354 is fixed to the bottom of the frame 1, and the identifier 351 is fixed on the mounting seat 352. The mounting seat 352 is connected to the adjustment seat 353 through a connecting rod 355. The adjustment seat 353 is clamped on the vertical rod 354. The identifier 351 can adjust the position of the identifier 351 relative to the correction platform 31 through the adjusting seat 353 and the connecting rod 355, including height, distance, and angle adjustment. The wafer is provided with a mark identification, which corresponds to the wafer placement area in the material box 52 one by one, and before measurement, the wafer mark, such as the wafer OCR mark, is identified by the identification component 35, which facilitates the control system to bind the measurement result with the mark of the corresponding wafer, and facilitates later retrieval, viewing, and processing.

[0050] like Figure 6As shown, the positioning assembly 1 33 includes a support block 3 331 and a telescopic clamp 332. A plurality of support blocks 331 are arranged along the circumferential direction on the top of the correction platform 31, and a plurality of telescopic clamps 332 are arranged along the circumferential direction on the outer side of the correction platform 31. Each support block 331 is arranged one-to-one with each telescopic clamp 332, and a support slope is arranged on the top of the support block 1 331, and an arc-shaped clamping groove is arranged at the clamping end of the telescopic clamp 332. When loading the wafer onto the correction platform 31, the robot 24 places the wafer on the support slope of the support block 331, and then starts the telescopic clamp 332, so that the plurality of telescopic clamps 332 move toward the center of the correction platform 31, and the support slope guides the wafer to move, so that the center of the wafer is aligned with the center of the correction platform.

[0051] Among them, Figure 6 As shown, a correction base 34 is provided under the correction table 31, and a telescopic module for driving multiple telescopic clamps 332 to move radially along the correction table 31 and a rotating component for driving the correction table 31 to rotate along the Z direction are provided in the correction base 34, thereby driving the wafer on the correction table 31 to translate and rotate to correct the position of the wafer.

[0052] Example 3

[0053] Based on the structure of embodiment 1 or 2, Figure 2 , 3 As shown in 7-10, the measuring mechanism 4 also includes a base 45, a movable module 46 and a rotary motor 47 located below the measuring table 41. A movable module 46 is provided on the upper side of one side of the base 45, and a platform for installing the spectrometer 42 is provided on the other side. The rotary motor 47 is fixed to the movable end of the movable module 46 through a motor mounting seat 471, and the measuring table 41 is connected to the output end of the rotary motor 47; a protective cover 472 covering the rotary motor 47 is also provided between the movable module 46 and the measuring table 41 to protect the motor; the movable module 46 drives the measuring table 41 to translate, and the movable module 46 adopts a linear motor module, which has the advantages of fast response speed, higher precision, high dynamic sensitivity, low noise, etc. compared with the linear module of the ball screw, thereby ensuring the position accuracy of the measuring point, and the rotary motor 47 drives the wafer on the measuring table 41 to rotate, thereby changing to different measuring points. A gold mirror assembly 48 for calibrating the optical path of the spectrometer 42 is also provided on one side of the motor mounting seat 471; the gold mirror assembly 48 includes a lifting cylinder 481 and a gold mirror 482. The lifting cylinder 481 is fixed on the motor mounting seat 471 through a cylinder mounting seat, and the gold mirror 482 is connected to the output end of the lifting cylinder 481 through the gold mirror mounting seat. The gold mirror 482 can be moved up and down by the lifting cylinder 481, so as to adjust the position of the gold mirror 482 and ensure the accuracy of the optical path of the spectrometer.

[0054] In the above structure, if Figure 2 ,7 As shown, the base 45 is an air-floating platform, and the four corners of the bottom thereof are provided with air-floating shock absorbers 49 fixed on the frame 1, and the air-floating shock absorbers 49 are connected to an external air source. The air-floating shock absorbers 49 can adapt to the pressure changes caused by the base 45 acting on the air-floating shock absorbers 49, thereby maintaining the horizontal state of the air-floating platform; therefore, the air-floating platform can not only adaptively adjust the horizontality of the base 45 and maintain the horizontal state of the base 45, but also reduce the vibration of the measuring platform 41 during operation, reduce damage to the equipment, and improve measurement accuracy.

[0055] In addition, if Figure 8-10 As shown, the measuring platform 41 is provided with a positioning assembly 2 43, and the positioning assembly 2 43 includes two fixed chucks 431 and a movable chuck 432 evenly distributed along the circumferential direction of the measuring platform 41, and the outer ends of the fixed chucks 431 and the movable chucks 432 are provided with arc-shaped support surfaces and stop-top platforms 4311 protruding from the support surfaces, and the movable chuck 432 is moved radially along the measuring platform 41 through a pushing assembly 44; the pushing assembly 44 includes a pushing cylinder 441, a wheel seat 442, a pushing wheel 443, a push rod 444, a slide seat 445, and a slide rail 446. The pushing cylinder 441 is fixed to the motor mounting seat 471 through a connecting plate, and a wheel is provided at its output end. The top of the wheel seat 442 is provided with a pushing wheel 443, the upper end of the pushing rod 444 is connected to the inner end of the movable chuck 432, and the lower end passes through the sliding seat 445 and abuts against the outer side of the pushing wheel 443, and the sliding seat 445 is inserted with a sliding rod 447, and the sliding rod 447 is inserted in the middle of the pushing rod 444 and is slidably connected to the pushing rod 444, and the sliding rail 446 is provided at the bottom of the movable chuck 432, and the top of the sliding seat 445 is provided with a sliding block slidably connected to the sliding rail 446, and the sliding rail 446 and the sliding rod 447 can play a guiding role to ensure that the movable chuck 432 moves along the radial direction of the wafer, thereby ensuring that the center of the wafer is aligned with the center of the measuring table 41 when the three chucks clamp the wafer.

[0056] When loading the material onto the measuring table 41, the robot arm 24 places the wafer on the supporting surfaces of the fixed chuck 431 and the movable chuck 432, and then starts the push cylinder 441 to move the movable chuck 432 toward the center of the measuring table 41, clamping the wafer between the stop table 4311 of the fixed chuck 431 and the movable chuck 432, and aligning the center of the wafer with the center of the measuring table 41.

[0057] The present invention also provides a working method of a wafer epitaxial film thickness measuring device, comprising the following steps:

[0058] S1, loading, the robot arm 24 clamps a wafer in the material box 52 of the loading table 5 and places it on the correction table 31, and then the positioning component 1 33 is started to position and fix the wafer on the correction table 31;

[0059] S2, correction, the correction mechanism 3 corrects the position of the wafer according to the detected reference position, and the recognition component 35 recognizes and records the wafer mark;

[0060] S3, material picking, the robot arm 24 goes to the calibration table 31 to pick up the material, the clamping assembly 25 on the robot arm 24 goes to the calibration table 31 to clamp the wafer, and then the positioning assembly 1 33 releases the positioning of the wafer to ensure that the wafer does not shift during the material picking process, and then the robot arm 24 places it on the measuring table 41, and the positioning assembly 2 43 on the measuring table 41 positions and fixes it on the measuring table 41; during the material conveying process, the material picking and placing positions are controlled by the program of the robot arm 24 itself to ensure the accuracy of the measurement position;

[0061] S4, measurement, the spectrometer 42 measures the epitaxial film thickness of the wafer according to the set measurement points, and binds the measurement results to the corresponding wafer marks; while measuring, the calibration mechanism 3 can calibrate again to save time.

[0062] Specifically, the measuring method is as follows: a plurality of measuring points are arranged on the wafer, the plurality of measuring points are distributed along the circumference of a plurality of concentric circles, the concentric circles are concentric with the wafer, an initial measuring point position is arranged on the innermost or outermost concentric circle, and the relative position of the initial measuring point relative to the center of the wafer and the reference position has been calibrated by the calibration mechanism 3 before the measurement; during the measurement, the spectrometer 42 is located directly above the initial measuring point, and the measurement is started from the initial measuring point first, and after the measurement, the measuring platform 41 is rotated by an angle, and other measuring points on the circumference where the initial measuring point is located are measured in sequence; after measuring the measuring points on the circumference of one concentric circle, the measuring platform 41 is translated so that the second concentric circle is located within the range of the spectrometer 42, and then the measurement of the measuring points on the second concentric circle is completed in sequence, until all the measuring points are measured; finally, the control system analyzes the distribution trend of the epitaxial film thickness according to the measurement result data corresponding to each wafer, thereby obtaining the epitaxial film detection result, and makes corresponding processing according to the detection result.

[0063] S5 , unloading. After the measurement is completed, the robot arm 24 places the measured wafer on the unloading table 6 .

[0064] The entire implementation process adopts intelligent unmanned operation, which is simple and convenient to operate, and improves the measurement accuracy and efficiency.

[0065] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0066] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A wafer epitaxial film thickness measurement device, characterized in that: The invention comprises a frame, a turnover mechanism, a correction mechanism and a measuring mechanism. A closed measuring chamber is arranged in the frame. A loading platform and an unloading platform are arranged in parallel on the outside of the frame. Both the loading platform and the unloading platform are provided with a material taking port connected with the measuring chamber. The turnover mechanism is arranged in the measuring chamber, and circulates between the correction mechanism, the measuring mechanism and the material taking ports of the loading platform and the unloading platform to transport materials. The correction mechanism and the measuring mechanism are also arranged in the measuring chamber and are arranged around the outside of the turnover mechanism. The correction mechanism comprises a correction platform and a sensor group. The correction platform is used to place wafers, and a positioning component 1 for positioning the position of the wafer on the correction platform is provided on the correction platform. The sensor group is arranged on the correction platform and is used to detect the reference position of the wafer. The correction platform can drive the wafer to rotate according to the detected reference position to correct the position of the wafer. The measuring mechanism comprises a measuring platform and a spectrometer. The spectrometer is arranged above the measuring platform and is used to measure the thickness of the epitaxial film of the wafer. The measuring platform is used to place the wafer and can drive the wafer to translate and rotate.

2. The wafer epitaxial film thickness measurement device according to claim 1, characterized in that: The measuring chamber is divided into measuring chamber 1 and measuring chamber 2 by a partition. The turnover mechanism and the correction mechanism are arranged in the measuring chamber 1, and the measuring mechanism is arranged in the measuring chamber 2. The partition is provided with a working groove for the mechanical arm of the turnover mechanism to pass through; the tops of the measuring chambers 1 and 2 are both provided with fans for clean measuring rooms.

3. The wafer epitaxial film thickness measurement device according to claim 1, characterized in that: The turnover mechanism includes a mobile module 1 and a robotic arm base. The mobile module 1 is fixed at the bottom of the frame, and a robotic arm base is provided at its output end. A lifting component is provided in the robotic arm base, and two robotic arms are provided at the output end of the lifting component. The two robotic arms take and put materials alternately.

4. The wafer epitaxial film thickness measurement device according to claim 3, characterized in that: The turnover mechanism also includes a clamping assembly arranged on the mechanical arm, and the clamping assembly includes a connecting arm, a telescopic rod, a push plate, and a support plate. The connecting arm is connected to the output end of the mechanical arm, and the support plate is a Y-shaped fork plate, whose main body end is connected to the connecting arm, and the top surfaces of the two fork-shaped plates at its forked end are provided with a support block 1, the push plate is arranged on the main body end of the support plate, and is slidably connected to the support plate through the telescopic rod inserted on the connecting arm, the support plate is also provided with a slide groove for guiding the sliding of the push plate, and the main body end of the support plate is also provided with a support block 2 located on both sides of the push plate, the top surfaces of the support blocks 1 and 2 are both provided with arc-shaped support surfaces, and the middle part of the support surface of the support block 1 is also provided with a stop block protruding from the support surface, and the push plate and the stop block cooperate to position the wafer placed on the support surface.

5. The wafer epitaxial film thickness measurement device according to claim 1, characterized in that: The correction mechanism also includes an identification component arranged on one side of the correction table. The identification component is used to identify wafer marks and includes an identifier, a mounting seat, an adjustment seat, and a vertical pole. The vertical pole is fixed to the bottom of the frame, and the identifier is fixed to the mounting seat. The mounting seat is connected to the adjustment seat through a connecting rod, and the adjustment seat is clamped on the vertical pole. The position of the identifier relative to the correction table can be adjusted by the adjusting seat and the connecting rod.

6. The wafer epitaxial film thickness measurement device according to any one of claims 1 to 5, characterized in that: The positioning component one includes a support block three and a telescopic clamping block. A plurality of support blocks three are arranged along the circumferential direction on the top of the correction platform, and a plurality of telescopic clamping blocks are arranged along the circumferential direction on the outer side of the correction platform. Each support block three is arranged one-to-one with each telescopic clamping block, and a supporting inclined surface is arranged on the top of the support block three, and an arc-shaped clamping groove is arranged at the clamping end of the telescopic clamping block.

7. The wafer epitaxial film thickness measurement device according to claim 6, characterized in that: A correction base is provided below the correction platform, and a telescopic module for driving a plurality of telescopic clamping blocks to move radially along the correction platform and a rotating component for driving the correction platform to rotate along the Z direction are provided in the correction base.

8. The wafer epitaxial film thickness measurement device according to claim 1, characterized in that: The measuring platform is provided with a second positioning assembly, and the second positioning assembly includes two fixed chucks and a movable chuck evenly distributed in the circumferential direction of the measuring platform, and the outer end portions of the fixed chuck and the movable chuck are provided with arc-shaped supporting surfaces and stop-top platforms protruding from the supporting surfaces, and the movable chuck moves radially along the measuring platform through a pushing assembly; the pushing assembly includes a pushing cylinder, a wheel seat, a pushing wheel, a pushing rod, a sliding seat, and a sliding rail. The pushing cylinder is fixed to the motor mounting seat through a connecting plate, and a wheel seat is provided at the output end thereof, and a pushing wheel is provided on the top of the wheel seat, the upper end of the pushing rod is connected with the inner end of the movable chuck, and the lower end passes through the sliding seat and abuts against the outer side surface of the pushing wheel, a sliding rod is inserted in the sliding seat, the sliding rod is inserted in the middle of the pushing rod and is slidably connected to the pushing rod, the sliding rail is provided at the bottom of the movable chuck, and a sliding block slidably connected to the sliding rail is provided on the top of the sliding seat.

9. The wafer epitaxial film thickness measurement device according to claim 1 or 8, characterized in that: The measuring mechanism also includes a base, a mobile module 2, and a rotating motor located below the measuring platform. The mobile module 2 is provided above one side of the base, and a platform for installing a spectrometer is provided on the other side. The rotating motor is fixed to the moving end of the mobile module 2 through a motor mounting seat, and the measuring platform is connected to the output end of the rotating motor; a protective cover covering the rotating motor is also provided between the mobile module 2 and the measuring platform; a gold mirror assembly for calibrating the optical path of the spectrometer is also provided on one side of the motor mounting seat.

10. The wafer epitaxial film thickness measurement device according to claim 9, characterized in that: The base is an air-floating platform, and air-floating shock absorbers fixed on a frame are arranged at the four corners of the bottom of the base, and the air-floating shock absorbers are connected to an external air source.

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